The action of ethacrynic acid on sodium efflux from single toad oocytes.
1. Ethacrynic acid (10(-3)M) at pH 7.4 caused approximately 83% inhibition of Na efflux from single dissected toad oocytes.2. Less inhibition was found at concentrations below 10(-3)M but higher concentrations did not cause greater inhibition.3. At an external pH of 7.0 the onset of inhibition was more rapid than at pH 7.4.4. Ouabain (10(-3)M) produced only 30% inhibition of the Na efflux, and the subsequent application of ethacrynic acid largely inhibited the remaining efflux.5. Application of ouabain, after ethacrynic acid had produced some 80% inhibition, caused only a further 9% drop in efflux.6. In uninhibited cells, Na efflux was found to be greater at pH 8.0, and less at pH 7.0 than at 7.4.
D000818:Animals; D001001:Anura; D001693:Biological Transport, Active / Q000187:drug effects*; D003864:Depression, Chemical; D004976:Ethacrynic Acid / Q000494:pharmacology*; D005260:Female; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D010042:Ouabain / Q000494:pharmacology; D010063:Ovum / Q000187:drug effects*; D012964:Sodium / Q000378:metabolism*; D012975:Sodium Isotopes; D013997:Time Factors
D012975:Sodium Isotopes; D010042:Ouabain; D012964:Sodium; D004976:Ethacrynic Acid